The present invention relates to a terminal box for hermetic compressors used for domestic refrigerators or for other applications which comprise a hermetic compressor.
Nowadays there are various ways and means to connect the terminal box to its compressor. The functions to be executed by the terminal box are on the one hand to receive the electric feeding line and the internal cablage and on the other hand to protect the components (starter and temperature relay) provided for starting and for electrical security.
During the installation phase, the hermetic compressor is connected, without terminal box-starter-temperature relay, to the refrigerator circuit by means of the welding of the suction and discharge lines, afterwards the operator installs the starter, the temperature relay and the terminal box in suitable seats near the compressor.
As the compressor must not jut outside of the refrigerator casing, the seats for the starter, the temperature relay and the terminal box are positioned in such a way that they are between the compressor and one of the two refrigerator casing's lateral walls. In such a disposition the operator locates the terminal box between the lateral wall and the compressor, inserting it in a suitable seat and moving it from the lateral wall toward the compressor. It is thus easily comprehensible that the free space between the compressor and the lateral wall must be enough so that it is possible to insert the electrical accessories first, that is the starter and the temperature relay, and then the terminal box. This requires a smaller utilizable space inside the refrigerator casing and if two compressors are used, for example when a freezer and a refrigerator are combined in the same casing but using two separate refrigerating circuits, this problem becomes even greater. In fact, in the combined application, it is necessary to use two compressors and terminal boxes of smaller dimensions or to increase the external volume of the casing.
Another drawback of the known terminal boxes is caused by the fact that, the line-pressers fixing the feeding and internal cablage lines are formed by small plastic junctions which press the lines against the terminal box by means of fixing screws. The line cablage and fixing operation in narrow and hardly reachable spaces for the operator require a considerable time for locating the compressor in the refrigerator casing.
Further, if the line-pressers are unbound and detached from the terminal box, and it is the same for the fixing screws, the difficulties are increased because it is necessary to handle small components. A further drawback of the known terminal boxes is that, when they are positioned on the compressor and the various electrical connections are fastened, it is necessary to protect the parts under tension by means of a plastic cover which is fixed to the terminal box by a spring or by screws. Also this operation results in difficulty for the above-mentioned reasons.
In order to complete the citation of the known art it is necessary not to forget that the management of the above-mentioned components (terminal box, terminal box cover, fixing spring or screw, line pressers, line presser screws and so on) is very complicated and expensive, as it involves the whole assembly process from beginning to end.